Smoking substitute apparatus

1. A smoking substitute apparatus having:

an air inlet;

an outlet;

a flow passage formed between the air inlet and the outlet;

a vaporization chamber in communication with the flow passage, the vaporization chamber having an aerosol generator configured to generate an aerosol from an aerosol precursor by heating,

wherein the aerosol generator comprises:

a vaporizer element loaded with aerosol precursor, the vaporizer element being heatable by a heater and presenting a vaporizer element surface to air in the vaporization chamber,

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 1.3 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 50° C. is not less than 16 ms.

2. The smoking substitute apparatus of claim 1 , wherein the cooling rate of the vapor is such that the time taken to cool to 50° C. is in a range from 16 ms to 0.5 s.

3. A smoking substitute apparatus according to claim 2 wherein, in an air flow rate between the air inlet and outlet of 1.3 L min −1 , the equivalent linear cooling rate of the vapor to 50° C. is not more than 5° C./ms.

4. A smoking substitute apparatus according to claim 2 wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 2.0 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 50° C. is not less than 16 ms.

5. A smoking substitute apparatus according to claim 2 wherein, in an air flow rate between the air inlet and outlet of 2.0 L min −1 , the equivalent linear cooling rate of the vapor to 50° C. is not more than 5° C./ms.

6. A smoking substitute apparatus according to claim 2 wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 2.0 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 75° C. is in a range from 4.5 ms to 0.5 s.

7. A smoking substitute apparatus according to claim 2 wherein, in an air flow rate between the air inlet and outlet of 1.3 LPM, the equivalent linear cooling rate of the vapor to 75° C. is not more than 10° C./ms.

8. A smoking substitute apparatus according to claim 2 wherein, in an air flow rate between the air inlet and outlet of 2.0 L min −1 , the equivalent linear cooling rate of the vapor to 75° is not more than 10° C./ms.

9. A smoking substitute apparatus according to claim 2 wherein the apparatus is operable such that the aerosol has a Dv50 of more than 1 μm.

10. A smoking substitute apparatus according to claim 2 wherein the apparatus is operable such that the aerosol has a Dv50 in the range 2-3 μm.

11. A smoking substitute apparatus according to claim 2 wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that, when the air flow rate inhaled by the user through the apparatus is 1.3 L min −1 , the average magnitude of velocity of air in the vaporization chamber is in the range 0-1.3 ms −1 .

12. A smoking substitute apparatus according to claim 2 wherein the aerosol generator comprises:

a vaporizer element loaded with aerosol precursor, the vaporizer element being heatable by a heater and presenting a vaporizer element surface to air in the vaporization chamber,

a vaporizer element region being defined as a volume extending outwardly from the vaporizer element surface to a distance of 1 mm from the vaporizer element surface,

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that, when the air flow rate inhaled by the user through the apparatus is 1.3 L min −1 , the average magnitude of velocity of air in the vaporizer element region is in the range 0-1.2 ms −1 .

13. A smoking substitute apparatus according to claim 2 wherein the aerosol generator comprises:

a vaporizer element loaded with aerosol precursor, the vaporizer element being heatable by a heater and presenting a vaporizer element surface to air in the vaporization chamber,

a vaporizer element region being defined as a volume extending outwardly from the vaporizer element surface to a distance of 1 mm from the vaporizer element surface,

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that, when the air flow rate inhaled by the user through the apparatus is 2.0 L min −1 , the average magnitude of velocity of air in the vaporizer element region is in the range 0-1.2 ms −1 .

14. A smoking substitute apparatus according to claim 2 wherein the aerosol generator comprises:

a vaporizer element loaded with aerosol precursor, the vaporizer element being heatable by a heater and presenting a vaporizer element surface to air in the vaporization chamber,

a vaporizer element region being defined as a volume extending outwardly from the vaporizer element surface to a distance of 1 mm from the vaporizer element surface,

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that, when the air flow rate inhaled by the user through the apparatus is 1.3 L min −1 , the maximum magnitude of velocity of air in the vaporizer element region is in the range 0-2.0 ms −1 .

15. A smoking substitute apparatus according to claim 2 wherein the aerosol generator comprises:

a vaporizer element loaded with aerosol precursor, the vaporizer element being heatable by a heater and presenting a vaporizer element surface to air in the vaporization chamber,

a vaporizer element region being defined as a volume extending outwardly from the vaporizer element surface to a distance of 1 mm from the vaporizer element surface,

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that, when the air flow rate inhaled by the user through the apparatus is 2.0 L min −1 , the maximum magnitude of velocity of air in the vaporizer element region is in the range 0-2.0 ms −1 .

16. A smoking substitute apparatus according to claim 2 wherein the aerosol generator comprises:

a vaporizer element loaded with aerosol precursor, the vaporizer element being heatable by a heater and presenting a vaporizer element surface to air in the vaporization chamber,

a vaporizer element region being defined as a volume extending outwardly from the vaporizer element surface to a distance of 1 mm from the vaporizer element surface,

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that, when the air flow rate inhaled by the user through the apparatus is 1.3 L min −1 , the turbulence intensity in the vaporizer element region is not more than 1%.

17. A method of operating a smoking substitute apparatus, the smoking substitute apparatus having:

an air inlet;

an outlet;

a flow passage formed between the air inlet and the outlet;

a vaporization chamber in communication with the flow passage, the vaporization chamber having an aerosol generator configured to generate an aerosol from an aerosol precursor by heating, the aerosol generator comprising a vaporizer element loaded with aerosol precursor and presenting a vaporizer element surface to air in the vaporization chamber,

the method including:

drawing air between the air inlet and outlet by user inhalation at a flow rate in the range 1.3 to 2.0 LPM;

heating the vaporizer element to release vapor;

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 1.3 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 50° C. is not less than 16 ms.

18. The method of claim 17 , wherein the cooling rate of the vapor is such that the time taken to cool to 50° C. is in a range from 16 ms to 0.5 s.

19. A method according to claim 18 wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 2.0 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 50° C. is not less than 16 ms.

20. A method according to claim 18 wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 2.0 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 75° C. is in a range from 4.5 ms to 0.5 s.

21. A smoking substitute apparatus having:

an air inlet;

an outlet;

a flow passage formed between the air inlet and the outlet;

a vaporization chamber in communication with the flow passage, the vaporization chamber having an aerosol generator configured to generate an aerosol from an aerosol precursor by heating,

wherein the aerosol generator comprises:

a vaporizer element loaded with aerosol precursor, the vaporizer element being heatable by a heater and presenting a vaporizer element surface to air in the vaporization chamber,

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 1.3 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 75° C. is not less than 4.5 ms.

22. The smoking substitute apparatus of claim 21 , wherein the cooling rate of the vapor is such that the time taken to cool to 75° C. is in a range from 4.5 ms to 0.5 s.

23. A method of operating a smoking substitute apparatus, the smoking substitute apparatus having:

an air inlet;

an outlet;

a flow passage formed between the air inlet and the outlet;

a vaporization chamber in communication with the flow passage, the vaporization chamber having an aerosol generator configured to generate an aerosol from an aerosol precursor by heating, the aerosol generator comprising a vaporizer element loaded with aerosol precursor and presenting a vaporizer element surface to air in the vaporization chamber,

the method including:

drawing air between the air inlet and outlet by user inhalation at a flow rate in the range 1.3 to 2.0 LPM;

heating the vaporizer element to release vapor;

wherein the air inlet, flow passage, outlet and the vaporization chamber are configured so that:

when the aerosol precursor is an e-liquid consisting of 1.6% freebase nicotine and the remainder a 65:35 propylene glycol and vegetable glycerin mixture, the e-liquid having a boiling point of 209° C., air being drawn into the air inlet at a temperature of 25° C., and the vaporizer operated to release a vapor of total particulate mass 5 mg over a 3 second duration from the vaporizer element surface in an air flow rate between the air inlet and outlet of 1.3 L min −1 , the cooling rate of the vapor is such that the time taken to cool to 75° C. is not less than 4.5 ms.

24. The method of claim 23 , wherein the cooling rate of the vapor is such that the time taken to cool to 75° C. is in a range from 4.5 ms to 0.5 s.